After re reading through your threads, I realize
1 you have a 86 Tuned port SBC
2 you should have a 16198259 ECM to run it
3 I did not see a Mass Air Flow sensor on the engine or in the airstream.
4 It has become obvious that you could also have god knows what for a wiring harness this could be 1 of 2 of your biggest problems.
I have seen you post several times and realize your head must be spinning.
Do you have any part of the harness that isnt plugged into a sensor or the computer.
Didnt you also say the ECM has 3 plugs and the harness has only 2?
Hmmmmmmm.

hello,
the harness has three plugs that are all pluged into the computer.the computer is for speed density[16198262] and it is running maf.it has a paneless harness that has wires cut.since the car is in storage,i cant do much work on it now,but this problem is driving me nuts.i keep going to look at it and just scratch my head.have found a hot rod shop close by and as soon as the roads get better,will take it to them and hope they can figure it out.
thanks for all your input.i have learned a lot.

TPI blows it does not flow enough air in stock form and the aftermarket solutions are very costly once you get everything purchased and installed. USally wiring harness, upper lower and throttle body need to be replaced along with injectors and computer just to hit 300 hp. then the troubles really start costing money.

Junk the TPI install carb and intake drive car for next 20 years without problems.

Some gotchas for tpi.

Wiring gets old and brittle and cant be repaired easily. corrosoin will finally end the wiring problems with a full on replacement that is not as easy as one might think.

For your current problem check all the grounds and make sure they are clean and brite if you have never done it before its a good project for the next time you see the car. At least you will have a direction that is not wrong even if it is not a solution.

TPI blows it does not flow enough air in stock form and the aftermarket solutions are very costly once you get everything purchased and installed. USally wiring harness, upper lower and throttle body need to be replaced along with injectors and computer just to hit 300 hp. then the troubles really start costing money.

Junk the TPI install carb and intake drive car for next 20 years without problems.

This is so obnoxious. The tpi is a decent system.
.
Op: what is your problem? We can't help you if you don't say what's wrong.
If you're running a cut harness then 99% of the time you have to have the computer tuned. Basically it's looking for signals that it's not getting.

This is so obnoxious. The tpi is a decent system.
.
Op: what is your problem? We can't help you if you don't say what's wrong.
If you're running a cut harness then 99% of the time you have to have the computer tuned. Basically it's looking for signals that it's not getting.

What part of the tpi is a good system? Mine was junk. Replacement cost was more than it was worth and a carb makes more power with less problems. The tpi does not flow is its most killing problem even with all the best stuff stock manifolds will not make much more than 300 hp no matter what mods are done sep for boosting it.

Now with boost they work ok. great for turbos give good low end tq. But for NA engine that will spin over 6000 rpm then the tpi will not work. They are so small the engine will not make power above 5K rpm some say 4K rpm is the max for the system. My vette came with the best gm had to offer it was still crap.

The simple fact is clear to anyone that has any knowledge of tpi. It is designed to make max power at 2500 rpm. below that is good above that is good. But get to far away and it will clogged your engine worse than running a two barrel carb. Most two barrels will flow more air than the stock tpi system.

Yeah good system but if you want power let it go. get a bigger manifold and tbi or lt1 or edelbrock system or just a nice big carb. all are way better. Carb only cost a few hundred bucks and your back on the road.

My neighbor had and irocz with the tpi engine. All he did was a cam and exhaust and that thing was definitely no slouch. For the average build it's a good setup and performs well. Plus it's very street friendly especially as a daily driver or such. Now if you were trying to put 500 to the wheels i can see that it will be a problem. But to get 400 crank hp shouldn't be a problem at all. Just like carburetors it will only support so much power. You can run a mild small block on a 600cfm but you'd definitely need to step up to a larger carb if you wanted more power. Same with the tpi. The stock setup can handle moderate power but it needs to be modified to make support higher power levels.
Saying the tpi sucks because it can't handle high hp is like saying tbi sucks for the same reason. Or that 2barrels suck cause they can't make 6million horsepower. Everything has it's purpose and the tpi does exactly what it was designed to do.

believe me,i don't take any thing the wrong way.i know you guys are trying to help,and I appreciate it.
I want to keep the t p I and am not concerned about speed.just like cruising and cruise nights.i have no preference in running maf or map.which ever will be the less costly.the cars runs fine,once warmed up,so I must be missing something.thanks for all your input.

After re reading through your threads, I realize
1 you have a 86 Tuned port SBC
2 you should have a 16198259 ECM to run it
3 I did not see a Mass Air Flow sensor on the engine or in the airstream.
4 It has become obvious that you could also have god knows what for a wiring harness this could be 1 of 2 of your biggest problems.
I have seen you post several times and realize your head must be spinning.
Do you have any part of the harness that isnt plugged into a sensor or the computer.
Didnt you also say the ECM has 3 plugs and the harness has only 2?
Hmmmmmmm.

Agreed. I have to admit that I missed the lack of MAF in the pics, but I'm in agreement that there is a mismatch of parts. OP put in an earlier thread that he has a 9th (cold start) injector and it is hooked up, but there wasn't any MAP systems that utilized the 9th injector.
As I mentioned in another of the OP's threads, getting some O2 datalogging info would be very beneficial as to why his engine runs poorly when cold. Also performing a pinout of his harness and comparing it to to stock pinouts should illuminate whether his harness has been modified.

Hopefully the shop that the car is going to be taken to is capable of doing these things. If so, then I'm sure the problem will be resolved.

Regarding, the 'obnoxious' comment, I don't know if I'd say obnoxious, but I would say close minded and I believe it is relatively egotistical to assume that everyone else wants what you want - to each his own

The Following 2 Users Say Thank You to 64nailhead For This Useful Post:

X2 with Nailhead. The TPI did what it was designed to do at the time is was built, and did it well.
80s cars lacked any power at all and the way to sell a performance car was to build it to run stop light to stoplight. The TPI works well to build torque and doesnt need to rev high to do it. That would also allow pretty decent mileage if just cruising.
They also look pretty cool , especially in street rods when some of the stuff is polished up.
Not my cup of tea, but I allways enjoy seeing them at the car show.
Helping a fellow hotrodder is important. If you dont like the build ...dont post.
Negativity usually comes from within someone who is unhappy with themself, so they try to make others unhappy , so they arent alone. Pretty sad.

believe me,i don't take any thing the wrong way.i know you guys are trying to help,and I appreciate it.
I want to keep the t p I and am not concerned about speed.just like cruising and cruise nights.i have no preference in running maf or map.which ever will be the less costly.the cars runs fine,once warmed up,so I must be missing something.thanks for all your input.

OK I dont have a lot of info to go on. But do see a few things to look at by reading what others have posted. If you have a 9th injector that is not firing then it will not run properly when cold. This is the cold start injector.

Wiring harness in cars under the hood really need to be soldered and taped and shrink wrapped just to survive a few years must less the life of the car. Twisted or using butt connectors will not work it will also have high resistence and not function properly. The older computers were even more likely to not be happy when the connection are corroded.

If your tpi computer is setup for maf and you have a map sensor tpi system from an older car you may want to buy an older ecu to match. Yes you can reprogram and all types of other crap but a new ecu from ebay is under 100 bucks and may solve the problem straight out. if the rest of the system is setup correctly. The ecu for any tpi system is based on the car. No cars from different models had the same ecu. Best to get the one that belongs in what ever type of car the tpi came from. If its all stock then you have another problem that must be address. But make sure its wired and setup correctly.

Some cars and truck have the same systems but they may be wired to different pins in the computer. this can and does change from year to year.

If you can give me a full list of years and makes of all cars the tpi is from and where all the parts came from i can probably figure out where the disfunction is. I am willing to bet its the 9th injector and just needs the correct model ecu installed.

Not to be harsh or obnoxous in 1990 tpi was bad arse. But now its not really easy to keep going or its not all that reliable once it starts to fail. I hate to tell someone advice that will lead them down a road of spending more money than they want. Over time the tpi will be a money pit or a source of frustration. But it does work good when properly setup. That being said my vette has a carb!

What part of the tpi is a good system? Mine was junk. Replacement cost was more than it was worth and a carb makes more power with less problems. The tpi does not flow is its most killing problem even with all the best stuff stock manifolds will not make much more than 300 hp no matter what mods are done sep for boosting it.

Now with boost they work ok. great for turbos give good low end tq. But for NA engine that will spin over 6000 rpm then the tpi will not work. They are so small the engine will not make power above 5K rpm some say 4K rpm is the max for the system. My vette came with the best gm had to offer it was still crap.

The simple fact is clear to anyone that has any knowledge of tpi. It is designed to make max power at 2500 rpm. below that is good above that is good. But get to far away and it will clogged your engine worse than running a two barrel carb. Most two barrels will flow more air than the stock tpi system.

Yeah good system but if you want power let it go. get a bigger manifold and tbi or lt1 or edelbrock system or just a nice big carb. all are way better. Carb only cost a few hundred bucks and your back on the road.

you can not get the low end ft lb that a tpi gets..
telling the guy to just install a carb. is somewhat silly.. as you don't know if he has to pass emmissions.. and opening the hood and the tester see'n a carb will be instant fail..
why the tpi wasn't used in trucks.. other than cost..
I'll never know..

I'm running a 92 TPI unit in my 4500 lb Chevy pickup and it does have the nice torque.
Mileage has increased since the swap as well and she runs smooth after installing a milder than the mild cam I had. I picked up more torque with that swap and hopefully a bit of mileage as well.

All this talk of wiring harnesses rotting and stuff is making me nervous though. I hope it doesn't turn to dust and fall off my truck.

I have had 2 injectors go on me and that is a pain. The design kind of sucks as the whole upper plenum needs to come off to get the fuel rails out.

I agree with lack of high HP. I have a dyno that shows how it drops off after 4000 RPM's.

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